Terminal portion of a robotic pick-up element provided with vacuum suction cups

ABSTRACT

A terminal portion for a robotic pick-up element lifts and transfers objects, the terminal portion lifts objects using vacuum suction cups. The terminal portion includes: a) a main unit, on the lower face of which are fixed a support suction cup and a vacuum transfer suction cup connected to the pneumatic equipment; b) a secondary unit, on the lower face of which are mounted a plurality of pick-up suction cups, the suction passages of which are connected to a single collecting passage opening into a hole on the upper face of the secondary unit which is smooth and shaped to adhere to the support cup and the vacuum transfer cup when they are placed next to it and the vacuum transfer cup of the main unit coaxially faces the hole of the secondary unit.

CROSS REFERENCE TO RELATED APPLICATIONS

The present Application claims priority to and includes by referenceInternational Application No. PCT/IB2004/004135 filed Dec. 10, 2004.

The present invention relates to the field of robotic systems which moveobjects according to predetermined programs, by lifting these objectswith pick-up elements and transferring them to positions other than theinitial positions in which they were picked up.

As is known, according to requirements, the operations described above,which are controlled and directed by an electronic computer, can becarried out along the two coordinate axes defining a horizontal plane oralong a set of three orthogonal axes.

More specifically, the invention relates to the terminal portions of theaforementioned pick-up elements. As those skilled in the art will know,these elements terminate in suction cups connected to pneumaticequipment which activates the suction cup by creating a vacuum insideit.

Depending on the type of object to be picked up, in other wordsdepending on the shape, the weight, the roughness of the outer surface,etc., suction cups with different characteristics have to be used, andthis makes it necessary to change them, possibly on many occasions,during a single operating cycle. This requires manual intervention by anoperator, with considerable loss of time. Above all, the fact that thesaid operator has to intervene within the operating area of a roboticsystem also entails a more than negligible risk of accidents.

The inventor of the subject of the present application has provided asolution to the problems described above, by devising a terminal portionof the type described above, but made in such a way that it can be usedfor a considerable number of objects of different types, because of thepossibility of replacing it rapidly and easily with other similarportions carrying suction cups of different types and/or sizes.

The inventor has devised a terminal portion for a robotic pick-upelement comprising a main unit provided with two suction cups, the firstof which acts as a support cup while the second acts as a vacuumtransfer cup. By means of the attractive force exerted by the firstsuction cup, the main unit is connected to, and supports, a secondaryunit which is provided with a plurality of pick-up suction cups ofdifferent types, and transfers the vacuum through the second suction cupto the pneumatic circuit terminating within the latter suction cups.

This can be done because the upper side of the secondary unit has a holewhich is connected to all the branches of the pneumatic circuit leadingto the said pick-up suction cups, this hole lying inside the said vacuumtransfer suction cup when the said main and secondary units areinterconnected as described.

By using a different secondary unit from time to time, it is thereforepossible to pick up and transfer objects of different types withouthaving to change any suction cups.

At the end of any given operating cycle, it is simply necessary to setthe secondary unit down on a suitable support, and pick up anothersecondary unit having a different set of suction cups, thus preparingfor the execution of another operating cycle with no significantdowntime.

The present invention therefore proposes a terminal portion for arobotic pick-up element as described in the attached claim 1.

A more detailed description will now be given of a preferred example ofembodiment of a terminal portion according to the invention, withadditional reference to the attached drawings, in which:

FIG. 1 is a schematic see-through front view of the said example ofembodiment, with the main unit separated from the secondary unit;

FIG. 2 is a view similar to that of FIG. 1, with the secondary unitconnected to the main unit which supports it.

As shown in the figures, the terminal portion 10 according to theinvention essentially comprises a main unit 5, on the lower face 5 r ofwhich there are fitted a support suction cup 1 and a vacuum transfersuction cup 2, connected pneumatically to equipment 4 of a known type(only indicated in a general way in the drawings) which can create thedesired level of vacuum in the cups.

The said terminal portion 10 also comprises a secondary unit 6, on thelower face 6 r are mounted a plurality of pick-up suction cups 3 i. Thelatter suction cups 3 i, although shown as substantially identical inthe drawings, can in fact also differ from each other, in such a way asto adhere to objects having particular shapes and/or physicalcharacteristics.

Suction passages 7 i terminating in each of the said pick-up suctioncups 3 i are formed in the aforesaid secondary unit 6, and these suctionpassages 7 i are connected to a single collecting passage 8 opening intoa hole 9 formed on the upper face 6 s of the said secondary unit 6,which is smooth and shaped in such a way that it can adhere to thepreviously described support cup 1 and vacuum transfer cup 2 of the mainunit 5 when placed next to them.

The terminal portion 10 according to the invention operates as follows:when an object 12 is to be picked up by the combined action of thepick-up suction cups 3 i of the secondary unit 6, the lifting element(not shown in the figures), carrying the main unit 5 at its free end, ismoved, while the said equipment 4 is activated in such a way as togenerate a vacuum (arrows E, F) within its support cup 1 and vacuumtransfer cup 2, and the main unit 5 is brought to a position above thesecondary unit 6. The said pick-up element is then used again to set themain unit 5 down on the upper face 6 s of the secondary unit 6, which issupported by a support housing 11 (FIG. 1), making the said support cup1 and vacuum transfer cup 2 adhere to this upper face. During theworking operation, the vacuum transfer cup must be positioned frontallyand coaxially with respect to the said hole 9 of the secondary unit 6.

The main unit 5 and the secondary unit 6, which are interconnectedpneumatically by the action of the support cup 1, thus form a singleassembly, as shown in FIG. 2, and the vacuum E present in the vacuumtransfer cup 2 is communicated through the said hole 9 (arrow H) to thecollecting passage 8 to which are connected the suction passages 7 i ofall the pick-up suction cups 3 i of the secondary unit 6, which aretherefore all activated by a vacuum (arrows G) and are thus able to pickup an object 12 adhering to them. By suitably positioning the terminalportion 10, it is therefore possible, as mentioned above, to pick up anobject 12 by means of the combined action of its suction cups 3 i, thecharacteristics of which have been selected according to the physicalcharacteristics of the object 12 to be picked up. This pick-up cantherefore be carried out in the most reliable way, and the liftingelement can then transfer the object, adhering to the terminal portion1, to any position other than the initial position in which it has beenpicked up.

On completion of the operation of picking up and transferring an object12, it is possible to continue by repeating the operation with othersecondary units carrying suction cups of different types, after eachsecondary unit 6 has be returned to its support housing 11 (FIG. 1).Clearly, the versatility of the system will be considerably enhanced bythe provision of a magazine (not shown in the drawings) housing aplurality of secondary units carrying sets of suction cups of differenttypes.

Evidently, in order to make it possible to carry out the operationsdescribed above, the upper face 6 s of the secondary unit 6 must besmooth, and its surface must be shaped in such a way that it can adhereperfectly to the bases 1 d, 2 d of the support cup 1 and the vacuumtransfer cup 2.

The simplest and most economical way of achieving this result, shownmore clearly in FIG. 1, is to make the said upper face 6 s of thesecondary unit 6 perfectly flat, and to form the support cup 1 andvacuum transfer cup 2 so that their respective bases 1 d, 2 d lie on aplane α parallel to the plane β on which the upper face 6 s of thesecondary unit 6 lies.

It is considered unnecessary to describe the part of the pneumaticsystem located upstream of the terminal portion 10 according to theinvention and its components, such as solenoid valves and the like,since it can be constructed by a person skilled in the art without theneed for any further explanation.

1. A terminal portion (10) of a robotic pickup element intended to liftobjects (12) and transfer them to positions other than the initialpositions comprises: a) a main unit (5), a main unit lower face (5 r) onwhich are fixed a support suction cup (1) and a vacuum transfer suctioncup (2) connected to a pneumatic equipment (4); b) a secondary unit (6),a secondary unit lower face (6 r) on which are mounted a plurality ofpick-up suction cups (3 i) which may be of different types, suctionpassages (7 i) which are connected to a collecting passage (8) openinginto a hole (9) formed a upper face (6 s) of the said secondary unit(6); and the upper face (6 s) of the secondary unit (6) being smooth andshaped in such a way as to be able to adhere to both said supportsuction cup (1) and the vacuum transfer suction cup (2) of the main unit(5) when they are placed next to it and the vacuum transfer suction cup(2) of the main unit (5) faces, and is coaxial with, the hole (9) of thesecondary unit (6), in such a way that the main unit (5) and thesecondary unit (6), are interconnected pneumatically by the action ofthe support suction cup (1), thus form a single assembly, wherein, theconnection between said terminal portion (10) and said objects (12)being made by the suction cups (3 i) in which a vacuum is created by thepneumatic equipment (4) through the hole (9) and the collecting passage(8) which are connected to the suction passages (7 i).
 2. The terminalportion according to claim 1, in which the upper face (6 s) of saidsecondary unit (6) is flat, and said suction support cup (1) and thevacuum transfer suction cup (2) terminate in their lower parts in bases(1 d, 2 d) lying on a plane (α) parallel to the plane (β) of said upperface (6 s) of the secondary unit (6).